1. Fire Doors by Fire-Resistance Rating

Fire doors are rated based on how long they can withstand a fire before they fail. The number next to the door’s name shows how many minutes it can resist fire:

• 20-minute fire-rated doors: FD20 AND 30 are typically used in areas with low fire risk, like homes or small offices.

• 45-minute doors: Common in hallways or between rooms.

• 60-minute (1-hour) doors: FD60 are installed in places that need more protection, like between different spaces or hazardous areas.

• 90-minute doors: FD90 are often found in stairwells or elevator shafts.

• 120-minute (2-hour) doors: FD120 are used in high-risk environments, like factories or areas storing hazardous materials.

These ratings help ensure the fireproof door can resist fire long enough to stop it from spreading while still maintaining its strength.

2. Fire Doors by Function (How They Operate)

Fire doors come in different styles, depending on how they open or close:

1. Swinging Fire Doors:

These are the most common type, opening and closing like a regular door. You’ll find them in homes, offices, hallways, and stairwells.

• With Regular Hardware:

These have standard door handles and locks, but are still rated for fire safety.

• With Fire Door Hardware:

These doors are designed as a complete fire-rated system, with door, frame, and hardware all tested to work together for maximum fire protection.

2. Horizontally Sliding Fire Doors:

These slide open and closed on a track, often used in large spaces like factories where a swinging door would take up too much room.

3. Vertically Sliding Fire Doors:

These doors slide up and down, similar to a garage door. They’re great for tight spaces like service counters or elevator shafts.

4. Rolling Steel Fire Doors:

Made from steel slats that roll up into a coil above the opening, these are typically used in warehouses or loading docks where large openings need to be secured.

5. Accordion or Folding Fire Doors:

These fold up like an accordion when open. They’re useful in places with wide openings, like auditoriums, where a standard door might be too large or impractical.

3. Fire Doors by Material 

Fire doors can also be classified by the materials they’re made from:

1. Timber (Wooden) Fire Doors:

Made from solid wood or wood-like materials, these are often used in homes or office buildings. They provide both fire protection and an attractive appearance.

2. Steel Fire Doors:

Made from steel, these doors offer stronger fire resistance and are commonly found in high-risk areas like factories or warehouses.

3. Glass Fire Doors:

These doors are made with fire-resistant glass, so they offer visibility while still providing fire protection. They’re often used in office buildings or areas where you need to see through the door but also need fire safety.

Standards, Testing, and Inspection of Fire-Rated Doors

1. Standards:

In the U.S., fire-rated doors must meet specific safety standards, including NFPA 80, NFPA 105, NFPA 252, UL 10B, and UL 10C. These tests are designed to assess how well the door performs in a fire, checking how long it can withstand heat and flames. They also include a hose stream test, where water is sprayed on the door to see how it handles the shock of sudden temperature changes.

2. Testing:

Fire-rated doors undergo rigorous testing to determine their fire endurance—this tests how long they can resist heat and flames without failing. In addition, the hose stream test evaluates the door’s ability to endure thermal shock, which happens when cold water is applied to the door’s hot surface, simulating the effects of fire-fighting efforts.

3. Fire Door Inspections:

Regular inspections are crucial to ensuring fire doors continue to perform as intended.

Here’s what to check for during an inspection:

• No damage: Ensure the door has no visible holes, cracks, or other surface damage.

• Parts intact: The glazing (glass) and frame should be intact and securely attached.

• Proper alignment: The door, frame, and hardware should align properly and function smoothly.

• Self-closing and latching: The door should close on its own and latch securely without any issues.

• No unauthorized modifications: The door shouldn’t have any alterations that could compromise its fire resistance.

Regular inspections are crucial to ensuring fire doors continue to perform as intended. These checks align with NFPA 80 standards, which include requirements like verifying fire door labeling, checking fire door rating labels, and ensuring self-closing mechanisms function properly.

How to Identify a Fire-Rated Door or What Makes a Door Fire-Rated?

Here is what makes a door a fire-rated door:

• Certification label: A label on the edge or frame of the door that shows its fire rating and the manufacturer’s details.

• Material: Fire doors are typically made from durable materials like steel, solid wood, or specialized composites that can withstand high temperatures.

• Special features: Many fire doors have intumescent seals that expand when exposed to heat, helping to block smoke and flames.

• Hardware: Fire doors often include self-closing mechanisms and latches to ensure they stay closed in the event of a fire.